Prior to setting a bone fracture, the fracture must be reduced. That is, the various bone fragments or pieces must be repositioned in their proper relative arrangement before the fractured bone can be fixed or stabilized for healing.
Various techniques exist for reducing bone fractures, one of which is disclosed in U.S. Pat. No. 5,122,146. In that patent, the fracture is reduced using, in part, a fracture reduction tool and a "guide wire". Through manipulation of the fracture reduction tool (and the help of an assistant if necessary), proper alignment of the fragments is achieved. The proper alignment is then maintained by the insertion of the guide wire through the medullary canal of each fragment.
Further reduction and preparation for stabilization is performed by reaming the medullary canal of the fragments that are now held in alignment. This operation is achieved by sequentially advancing and retracting a series of hollow reaming instruments over the guide rod. With the use of each successive reaming instrument, the medullary canal is increased in size until it is enlarged sufficiently to receive a nail or pin that will permanently keep the bone fragments in proper alignment and thereby stabilize the bone for healing.
Although not mentioned in U.S. Pat. No. 5,122,146, in practice, the use of a guide wire in the reduction of fractures can prove highly disruptive. Most frequently this occurs during the reaming operation where the reaming instruments are being advanced and retracted over the guide wire.
Since the guide wire is not secured in position within the medullary canal during the reaming operation, retraction of the hollow reaming instrument, through contact with the guide wire, often pulls the guide wire out of position, even when the surgeon is using extreme caution. When this occurs, the entire reduction procedure must be started again thus obviously leading to greater risk of damaging the fractured area as well as increasing the time required to complete the procedure.
No guide wires of the known prior art have provided any acceptable solution to this problem. The guide wire of U.S. Pat. No. 5,122,146 includes a bead-tip at its distal end, however the function of the bead-tip is primarily to prevent the reaming instrument from being advanced too far within the medullary canal; it does not secure the guide wire within the canal.